List-Unsubscribe
A header field (RFC 2369) giving mail programs a way to unsubscribe the reader, as a mailto: address, an https: link or both; it powers the unsubscribe button in Gmail and others.
What it means
List-Unsubscribe holds one or more URLs in angle brackets, separated by commas. A mail program that supports it can show its own unsubscribe control near the sender name, so the reader does not have to find the link in the footer. Gmail shows that control only for messages that pass its automated eligibility checks.
With the List-Unsubscribe-Post header added, the https URL becomes a one-click unsubscribe under RFC 8058. Google requires that for marketing and subscribed messages from senders of more than 5,000 messages a day to Gmail accounts. Yahoo requires bulk senders to have a working List-Unsubscribe header that supports one-click unsubscribe, recommends the RFC 8058 POST method and accepts mailto. Both also ask for a visible unsubscribe link in the body; Google recommends honouring requests within 48 hours and Yahoo asks for 2 days.
Example
List-Unsubscribe: <https://example.com/u/7f3a9c>, <mailto:unsubscribe@example.com?subject=7f3a9c>Related terms
On this site
Sources
What this definition rests on. The wording is ours; the facts are theirs.
- RFC 2369: The Use of URLs as Meta-Syntax for Core Mail List Commands and their Transport through Message Header Fieldsrfc-editor.org
- RFC 8058: Signaling One-Click Functionality for List Email Headersrfc-editor.org
- Google, Gmail Help: Email sender guidelinessupport.google.com
- Google, Gmail Help: Email sender guidelines FAQsupport.google.com
- Yahoo Sender Hub: Sender best practicessenders.yahooinc.com
All 432 terms in the glossaryThe wiki: blocklists and bounce codes